Le dim. 13 avr. à 22:36, zerfetzen a écrit : > > Hi, > I'm very new to R and absolutely love it. Does anyone know how to use > something in R that functions like a BY command in SAS? > > For example, let's say you have a variable x, and you want to see > the mean. > Easy... > >> mean(x) > > But what if you want to see the mean of x conditional on another > discrete > variable? My best attempts so far are something like... > >> mean(x, y_cat=1) > > ...which of course doesn't work. I have downloaded plenty of R user > guides > that are very informative, but am not seeing much on detailed > descriptives > or data manipulation (for my life, I can't figure out how to sort an > attached data frame, but that's another issue). Thanks.
You didn't give much detail about what exactly you want to do (have a look at the Posting Guide), but... perhaps by() will do what you what. See ?by . Bye! --- Vincent Goulet, Associate Professor École d'actuariat Université Laval, Québec [EMAIL PROTECTED] http://vgoulet.act.ulaval.ca ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.